WANG Huaming Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaZHANG Qing Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
ChinaSHAO Hesheng Beijing Graduate School
,
China University of Mining and Technology
,
Beijing
,
China Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The role of austenite in impact-abrasion process was studied on the basis of the impact-abrasion test results of a newly developed austenite-bainitic ferrite dual-phase abrasion-resistant steel with high strength,high toughness and high strain-hardening ability. It is found that the morphology,distribution and mechanical stability,rather than the volume fraction,of austenite govern the impact abrasion behaviour.Only the appropriate amount of fine and evenly dispersed austenite with adequate mechanical stability in high strength matrices,contribute effectively to the irnpact-abrasion resistance of the materials.While large quantity of coarse austenite with poor mechanical stability,especially when it acted as a continuous matrix of the material,is extremely detrimental to impact-abrasion resistance.
关键词:
austenite
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null
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null
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null
QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China
金属学报(英文版)
The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.
关键词:
stress corrosion cracking
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null
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null
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Materials and Corrosion-Werkstoffe Und Korrosion
Carbon steels were pre-corroded in atmospheres containing certain pollutants such as sulfur dioxide or hydrogen sulfide or nitrogen dioxide for certain period of time. Then the pre-corroded samples were further exposed at two central test stations in the country to evaluate the influence of pre-corrosion on the behavior of long-term atmospheric corrosion of carbon steel by gravimetric measurement and rust examinations with FT-IR and XRD. The results showed that the corrosion rates of every kind of carbon steel at Jiangjin station were two times higher than that at Beijing station. The influence of different pre-corrosion conditions on the long-term atmospheric corrosion of carbon steel was analyzed. It followed that the pre-corrosion conditions made the long-term atmospheric corrosion performance of three kinds of carbon steels different, but the differences were small. Among the three pollutants, NO2 showed the strongest influence to the process. As the exposure time was going on, all the samples corroded slowly at Beijing and Jiangjin stations.
关键词:
pollution parameters;prediction;outdoor;rust
